Methods: We included 40 healthy Caucasian men and postmenopausal women over the age of 50 (age 60±6 y, BMI 25.1±3.4 kg/m², 30 females) in a randomized, controlled, prospective, cross-over study (NCT01188902). Each subject followed a nut-free Western-type diet during a 2 week run-in period. Thereafter, subjects were randomized to 2 different diet phases, each lasting for 8 weeks (separated by a 2 week wash-out). One group (n=18) first followed a diet with walnuts (43 g of shelled walnuts/day) and then switched to an individually prescribed, nut-free Western-type (control) diet. The other group (n=22) followed the diets in reverse order. At the start and end of each diet phase, subjects received a standardized test meal (1100 kcal; 72% fat, 4% protein and 24% carbohydrate). Blood was drawn at 0 (fasting), 15, 30, 60, 120, 180, 240, 360, and 480 minutes. Total cholesterol (TC), LDL-cholesterol (LDL-C), HDL-cholesterol (HDL-C), triglycerides (TG), VLDL-TG, glucose, insulin, HOMA and QUICKI were determined in fasting samples. Area under the curve (AUC) and incremental AUC were calculated for postprandial TG, VLDL-TG, chylomicron-TG, glucose and insulin.